New guy from Ontario

[Go Go Diablo]

That thumb throttle is an interesting modification. I don't remember talking about this before, but here is something for all to think about.

The throttle shaft of the Tillotson carb has the return spring loaded on it. At least on a Diablo, this is the only mechanism to return the carb to an idle. Should the spring break, you better hope your brakes are in great shape so you can yank hard and hopefully shut off the key switch. Otherwise, bailing off and watching your Diablo run into the closest expensive thing is always an option too.

So I typically add another secondary return spring between the throttle shaft and heat shield.

So back to the thumb throttle. Yes, I like it better in most cases. But after a number miles on a long day of riding, your thumb is ready to fall off due to the fatigue of pushing the throttle. Of course, having this secondary return spring only makes that worse. So I've always thought about setting up a Diablo with both a thumb throttle and a half moon throttle. Seems the best of both worlds......right? I mean, what could go wrong?

DSC03755.JPG (164.25KiB)Viewed 11602 times

[jayvee43]

Should the spring break, you better hope your brakes are in great shape so you can yank hard and hopefully shut off the key switch. Otherwise, bailing off and watching your Diablo run into the closest expensive thing is always an option too.

I wonder Bruce, has this ever happened to anyone you know?

This last statement makes me think however. Should we have an "emergency kill switch" on our handles near where we put our hands? Like any other snow mobiles out there. There is a key switch to keep the kids from joy riding, but there is also a safety switch, Heck some now have safety lanyards with emergency shut off if you fall off.
You're scenario has me thinking. I would not like it very much if I got to stand by while my diablo took off aiming at the most expensive thing around. (more to follow on this tough)

Anyway. Today I was able to use the 20 ton press at work to disassemble my sprockets. I followed the directions on gogodiablo.com gear case dis assembly procedures and using the bearing separator turned upwards, I was rewarded with a pair of used cores I can trade in.
Here's a quick picture of the rest of my gear box parts. Now the fun begins. I have to shop for some parts. Hum!

[BillNH]

I have actually chased a Hus ski across a field when the throttle return spring came off during chain realignment activities. My father chased the same machine thru a field of cow manure for the same reason, we permanently fixed the spring after that one.

[Roy Teske]

Hi Jesse. It's for the best to OH the chaincase now. You'll be good for another 40 yrs. I would suggest you drill a filler hole in the top of the aluminum case , like the 502s. Much easier to fill. The last time I had my case apart, I also moved the level check hole to the front, ahead of the axle and just below the seal . I welded a 6mm nut on the back of the cover and used a bolt for the plug. Don't use the old chain, even if it looks good. The rollers tend to crack. Hope this helps.

Roy

[jayvee43]

Hi Roy.
I agree with the oil fill and level plug. And this brings me to a couple of questions.

1. Other than E-Bay or having to wait till my next Gogodiablo order; In Ottawa, is there a place where I can purchase the TIMKEN part #473237 oil seal that goes in the chain case lower cover?

2. Is a #50 roller chain with a quick connect acceptable? They don't have to be a endless chain now do they?

Again Thanks guys. I know I have so many questions. ( I feel like I am a step behind everybody "walking in your steps")

[jayvee43]

OK, Spent another hour in the shop. It's too damp and cold to be comfy.

I made a cork gasket out of 1/16th paper. Is there a flange sealer that you guys add to this gasket?

Also, Notice my drive sproket axle. The right side-end where the "E" clip is supposed to go is questionable. i am thinking of drilling right into the end, and tapping for a retainer bold and washer. What do you guys think?

My cut out gasket


My axles Left with the E clip groove ok


and this is the damaged E clip groove. It has a pin hole at the center. Should drill ok i think!

[Roy Teske]

Jesse
General Bearing on Kent Street in Ottawa will have the right seal and I bought my chain there also. Best to call ahead and make sure they have things in stock. I also got an oil-lite brass bushing there for the chain adjuster gear. I used a Toyota oil pan sealer on my cover. No gasket. When that stuff sets, you don't need the cover bolts, it's that strong. I would use some kind of sealer with the gasket, but it may not be necessary. As far as the axle goes, I secured my brake disc to the end of the jack-shaft with a 6mm bolt, washer and loc-tite. It's never come loose. I don't see why it wouldn't work on an axle. Another important thing is make sure your new sprockets fit tight on the axle. I got some over-sized woodruffe key stock and cut and filed new keys to fit the worn axle and hub grooves. Put a few spots of weld inside the hubs to tighten them on the axle and use loc-tite retaining compound 609 (?? I think that's the number). Bruce has an article on the site on doing this. My hubs have never come loose since. General Bearing also carries the woodruffe key bar stock and loc-tite 609. Perhaps Bruce can add to this.

Roy

[Go Go Diablo]

Those bearings and seals are common which is why I supply the numbers. If you can get them locally, no need for me to sell them and mark them up.

I do use Blue Permatex when I assemble a gearbox. I stay away from sealer that is also a significant adhesive because the next poor guy that has to get the cover off will have to bend it all up to get it off. So put a bead of blue permatex on the gearbox face, install the gasket, then add another bead on the gasket. Install the top cover. Put a bead of permatex on the top cover where the bottom cover overlaps it with a little extra on each side of this overlapping part and then install the bottom cover. Tighten the bolts snug and let the sealant form up. After about an hour, tighten down the cover bolts.

Putting a 1/2" fill hole in the top of the cover is a great suggestion. I do it to all my 500 gearboxes.

I think you have an old adjuster sprocket. The flat plate on it is quite short and may not cover the slotted hole. Check it and you may want to make a new plate that is longer and then cut it to size once you get it in and know where it needs to go.

I use endless chain rather than worrying about a master link that might fall off. If you have a chain separator, you can make your own endless chain which is what I supply when someone asks for a chain.

The driveshaft on the 500 gearbox only uses small snap rings for the sprocket retainers. It would be a good idea to get those grooves widened and then use a standard size 1" E Clip which is what the 502 & 503 use. With that said, drilling and tapping a hole for a bolt is a good idea too.

Regarding tight sprockets, you are getting new ones, so they should be tight unless your shaft is worn. The retaining compound works good if needed.

Hope that helps,

Bruce

[jayvee43]

Yup, this info helps a lot. thanks to both of you.

I was thinking of using the RTV Silicone already, so That settles it. I was also wondering why the adjuster slot was bigger than the steel slide, now I know. I'll make another longer one.

As for the chain and seal, I already went ahead and ordered it locally. I found it here in Renfrew at my local Case New Holland tractor dealer.

I may wait to drill and tap the drive sprocket shaft, until I receive the new sprockets and try opening the grooves to accommodate the new E clips securely.

In the mean time, I won't be doing much with the diablo for a while, i am going back to work. So not much time off anymore.
I'll surely post more pics as time goes by, so stay tuned.

Jesse

[jayvee43]

OK, I finally got all the parts for the gear case in place. Nothing special to report that any body has not covered already. With the exeption that I fabricated a Idler adjuster bar that covers the entire slot space, preventing snow and anything from getting in.
Also, I drilled and tapped the fill hole at the very top as advised by others. On the 4 X 4 Piece of wood on the last picture you can see the original size of the adjuster slide bar. It was way too small.

Here is a few pics.